JPH06288Y2 - Railway signal light drive circuit - Google Patents

Description

TECHNICAL FIELD The present invention relates to a railroad signal light drive circuit using a control rectifying element such as a thyristor for blinking and displaying the light (railroad signal light) of a railroad signal.

2. Description of the Related Art As a method of operating a railroad traffic signal, particularly overseas, the train may speed up when the traffic light is on, or when the traffic light is blinking. Has also adopted an indication operation method that requires speeding down.

Many of the driving circuits for blinking the signal light employ a configuration using a rectification control element such as a thyristor or triac, and apply a voltage (lighting instruction) externally applied to the series circuit of the rectification control element and the signal light. The signal lamp is blinked by allowing the rectification control element to pass in the same cycle by a gate control signal input from the control rectification element gate circuit to the rectification control element in a predetermined cycle. Here, the rectification control element refers to a semiconductor element having a control gate terminal typified by a thyristor (SCR), and the other two terminals are made conductive / non-conductive by the gate input. Triac etc. shall be included.

Problems to be Solved by the Invention By the way, a blinking drive circuit (flasher circuit) with a thyristor or a triac used in a conventional traffic signal
Has the following problems. In other words, when a short-circuit fault occurs in the thyristor (or triac), the traffic light indication will continue to light up, but this situation will occur regardless of the situation if the railway is operating as indicated above. Since it will be a message that can be upgraded, a train running in a very dangerous state is extremely unsafe and may cause a serious accident. However, the conventional traffic lights have not been devised so as to be fail-safe against the short-circuit failure.

The present invention has been made in view of the above circumstances,
It is an object of the present invention to newly propose a railroad signal light drive circuit that works in a fail-safe manner against a very dangerous short-circuit failure of a rectification control element and does not continuously light a signal light.

Means for Solving the Problems According to the present invention, the above problems include a railway signal light driving circuit, a control rectifying element gate circuit (1), a control rectifying element (2),
Slow release relay (Ry) with operating contact (Rya) and operating resistance
(R) is a railroad signal light drive circuit, comprising a control rectifier (2), an operating contact (Rya), and a signal light from a predetermined power supply terminal.
(L) are connected in series in order, and the slow release relay is connected to the control rectifier (2).
(Ry) is connected in parallel, the operating contact (Rya) and the signal lamp (L) are connected in parallel, the operating resistance (R) is connected in parallel, and the control rectifying element gate circuit (1) generates a control signal of a predetermined cycle. The control rectifying element (2) is an element whose both ends are conducted in response to a control signal from the control rectifying element gate circuit (1), and the slow release relay (Ry) is a control rectifying element (2). ) In parallel, and at the time of restoration, after a predetermined delay time has elapsed, the operating contact (Ry
The solution is to adopt a configuration that opens a).

With the above configuration, when power is normally supplied from the outside (drive instruction), the control rectifying element repeats conduction / non-conduction in response to the control signal from the control rectifying element gate circuit, and correspondingly to the output side. The power supplied from the power supply to the connected signal light from the power supply via the operation contact continues (accurately, increases or decreases as a result of passing or not passing through the drive coil of the slow release relay), and the signal light blinks. At this time, even in the cycle in which the voltage across the slow-release relay disappears, the operating contact delays and does not drop (open) so that lighting is not hindered.

On the other hand, when a short-circuit fault occurs in the control rectifying element, the voltage across the slow-release relay permanently disappears, so the operating contact opens after the delay operation, and the signal line from the power supply is cut off, so the light is surely turned off ( Safe side) and fail safe.

In addition, when supporting an AC power supply, control rectifier (2)
The slow release relay (Ry) is connected in parallel via the bridge rectifier circuit (3).

Embodiment Hereinafter, the present invention will be described based on an embodiment shown in the drawings.

The railway signal light drive circuit shown in the figure is a slow release relay (Ry) and an operating resistor (R) equipped with an operating contact (Rya) in addition to a control rectifying element gate circuit (1) and a controlling rectifying element (2). And includes another rectifier circuit (3).

One end (INa) of the input to which an external power source (blinking operation instruction signal: AC is possible in the example) is connected to a triac (2) that is a control rectifying element to support AC, and the other end The operating contact (Rya) of the slow release relay (Ry) is connected in series, and the other end is one end (OUTa) of the output. A signal lamp (L) is connected in series to this output terminal to form a series circuit section (SR). A slow release relay (Ry) is connected in parallel to the triac (2), but in the embodiment, the coil of the slow release relay (Ry) is a bridge rectifier circuit (diode bridge ((3 ) That is, the AC terminal of the rectifier circuit (3) is connected in parallel to both ends of the triac (2), and the slow release relay (Ry) is connected between the DC terminals. , Slow release relay (R
y) operates in parallel with TRIAC (2). Further, the operating resistor (R) is connected in parallel to the operating contact (Rya) and the signal lamp (L) that are connected in series.

The slow release relay (Ry) does not immediately recover when the input voltage is cut off by the delay relay, but recovers after a certain time (slow release time, delay time: described in detail later). Therefore, the opening of the operating contact (Rya) is delayed. The control rectifier element gate circuit (1) generates a gate control signal at a predetermined cycle by applying power and inputs it to the gate terminal of the triac (2) .It is composed of, for example, a flip-flop circuit and is appropriately specified as a signal lamp. Properly utter a pulse (gate control signal) at the cycle and input it to the triac (2).

As is well known, both ends of the triac (2) become conductive (AC is possible) in response to a gate control signal from the control rectifying element gate circuit (1). The operation resistance (R) is connected between the contact of the triac (2) and the operation contact (Rya) of the slow release relay and the ground (G) (output side), and is independently connected during the initial operation of the circuit. ) Load resistance and operate the slow release relay (Ry).
After the operation of the slow release relay (Ry), the operation contact (Rya) is closed and the signal lamp (L) also serves as the load resistance of the slow release relay (Ry).

As described above, the circuit of the embodiment has a gate circuit for a controlled rectifying element that generates a gate control signal at a predetermined cycle (1), a triac (2) that conducts at both ends according to the input gate control signal, and a recovery circuit. Occasionally, a contact is activated after a specified delay time
A slow release relay (Ry) for opening (Rya) is provided with an operating resistor (R) and a bridge rectifier circuit (3), and the above-mentioned predetermined connection is made.

Operation The operation of the railway signal light drive circuit of the embodiment will be described below.

In a normal state without failure, for example, when an AC voltage is applied to the input terminal from the power source as an external control condition (drive instruction),
The triac (2) is initially in a non-conducting state, and the current from the power supply is, for example, in the case of anti-cycle, connection point (a) -connection point (b) -connection point (c) -slow release relay (Ry) -connection. Point (d)
-Connection point (e) -Connection point (f) -Operating resistance (R) flows in this order, the slow release relay (Ry) operates, the operating contact (Rya) is closed, and the signal lamp (L) from the input terminal. To the output circuit (series circuit portion SR).

On the other hand, the control rectifying element gate circuit (1) also starts operating. Then, a pulse signal (gate control signal) is generated, the triac (2) is turned on correspondingly, and the voltage between terminals (voltage drop) becomes almost OV as shown in FIG. 2 (left half). At this time, an output voltage close to the input voltage is obtained on the output side and applied to the signal lamp (L) (and the operating resistance), and a sufficient current flows and the signal lamp (L) lights up.

Next, when the gate control signal is no longer applied to the triac (2), the triac (2) becomes non-conductive and the signal lamp
Since power is supplied to (L) through the internal resistance of the slow release relay (Ry), the current is reduced and the lamp filament of the signal lamp (L) hardly lights up (lights off).

In the present invention, the slow release time of the slow release relay (Ry) is selected to be longer than the conduction time of the triac (2). Therefore, the sufficient current is not supplied to the slow release relay (Ry), so it tries to recover when lighting, but it tries to recover with a delay time longer than the lighting time (triac conduction time), so the operating contact (Rya) opens. The output circuit is continuously maintained. By the way, if a relay having no slow release time is used, the relay repeats operation and restoration in a blinking cycle, which is not preferable in terms of reliability.

After all, in the normal state, as shown in the first half of FIGS. 2A to 2D, the above-described process is repeated depending on the presence or absence of the gate control signal (pulse) output from the control rectifying element gate circuit (1), The signal light (L) blinks (flasher).

Next, if the triac (2) has a short circuit fault, the second
As shown from the latter half of the figures (a) to (d), continuous alternating current is sent to the output side, but when a short circuit occurs, the resistance values at the connection points (a) and (f) become almost 0, and Since the current required for operation does not flow to the connected slow release relay (Ry), the slow release relay (Ry) is restored after the elapse of a predetermined delay time, the operation contact (Rya) is opened, the output circuit is opened, and the signal lamp No current is supplied to (L). After all, in the event of a short-circuit failure of the triac (2), the signal lamp (L) cannot be reliably turned on, which is a safe state and a fail sail (see FIG. 2).

Even if the triac (control rectifier) (2) has an open circuit failure, the signal light will only flow the current via the slow release relay (Ry), and it will always be off (safety side) because no sufficient current will flow. .

As described above, according to the railway signal light drive circuit of the embodiment, even if the triac (2) fails, the output side signal light (L) does not light up, and it is safe to use for train operation on the railway. .

In the embodiment described above, the external power source that serves as the control input may be DC. Further, although the triac is used as the controlled rectifying element, the same effect can be obtained by using the thyristor having the same controlled rectifying element. The thyristor has a directional property, but there is no problem even if it is operated by an alternating current as long as it is within the withstand voltage, and if the half-wave operation is avoided, it is 2
It is sufficient to use two thyristors as a pair.

If the slow release relay is non-polar, the bridge rectifier circuit
(3) is not particularly necessary, and even if it is a polar slow release relay, if the power source is only DC, the bridge rectifier circuit (3) is not always necessary, and the polarity of the slow release relay is used as the power source. It may be connected in parallel to the controlled rectifying element according to the polarity of.

Further, the control rectifying element gate circuit in the embodiment is configured to start operation by receiving an external power supply serving as a control input, but it may be operated by always supplying an appropriate separate power supply. The signal lamp will not light up without the supply of external power as an input.

Effects of the Invention As described above, the railway signal light drive circuit of the present application includes the control rectifying element gate circuit (1), the control rectifying element (2),
It has a slow release relay (Ry) equipped with an operating contact (Rya) and an operating resistor (R), and a control rectifying element (2), an operating contact (Rya) and a signal lamp (L) are in order from a predetermined power supply terminal. It is connected in series, the slow release relay (Ry) of the controlled rectifier element (2) is connected in parallel, and the operating contact (Rya) and signal lamp (L) are connected in parallel and the controlled rectifier is connected. The element gate circuit (1) generates a control signal of a predetermined cycle, and the control rectifying element (2) is an element whose both ends are conductive according to the control signal from the control rectifying element gate circuit (1). Since the slow release relay (Ry) is connected in parallel to the control rectifier (2) and the operating contact (Rya) is opened after the elapse of a predetermined delay time at the time of restoration, continuous lighting of railway signal lights It is useful as a signal light under the operating method in which the signal light is on the non-safe side, and even if a short-circuit fault occurs in the control rectifying element, the signal light will be the connecting point as before. There is an effect that become possible without reliably Fueirusefu railway signal lights to be turned off normally can be achieved.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an embodiment of a railway signal light drive circuit of the present invention, and FIG. 2 is a time chart of the circuit of FIG. 1 in a normal state and at the time of failure. (1): Controlled rectifier gate circuit, (2): Triac (controlled rectifier), (3): Bridge rectifier circuit, (R): Operating resistor, (Ry): Slow release relay, (Rya): Operation contact of slow release relay, (SR): DC circuit part, (L): Signal light,

Claims (2)

[Scope of utility model registration request] 1. A slow release relay (Ry) equipped with a control rectifying element gate circuit (1), a control rectifying element (2), and an operating contact (Rya).
And a resistance (R) for operation, which is a railway signal light drive circuit, in which a control rectifying element (2), an operation contact (Rya), and a signal light (L) are sequentially connected in series from a predetermined power supply terminal. The slow release relay (Ry) is connected in parallel to (2) and the operating contacts (Ry
a) and the signal lamp (L) are connected in parallel with the operating resistor (R), the control rectifying element gate circuit (1) generates a control signal of a predetermined cycle, and the control rectifying element (2) Is a device whose both ends are conducted in response to a control signal from the control rectifying device gate circuit (1), and the slow release relay (Ry) is connected in parallel to the control rectifying device (2) and has a predetermined value when restored. Operating contact after delay time path (Rya)
The drive circuit for railway signal lights that opens the door. 2. The railway signal light drive circuit according to claim 1, wherein the slow release relay (Ry) is connected in parallel to the control rectifying element (2) through a bridge rectifying circuit (3).